Mordant, Morbid and Maudlin

I found these growing in the gutter, up by the village green. A quick scratch around on Google brought up Redshank, or Lady’s Thumb. A peruse of its edibility rating found it in the, edible-but-I-don’t-know-why-you’d-bother category, when you add that it’s also in the, not-recommended-for-people-with-gout section, I began to wonder if I should have bothered to take the photograph. But wait, all is not lost, it makes a yellow dye when alum is used as a mordant.

Morbid (non-medically) is an unhealthy preoccupation with dying. When it come, to dyeing, you can use salt or vinegar to help the dye to penetrate the fabric but this doesn’t ‘set’ the dye and it will soon wash out. To fix the dye firmly in the cloth, you need to involve the dye in a chemical reaction, which will hook the colour molecules round the material fibres. There is a way to do this, by boiling the cloth in a very large pan of urine. As it takes a while to accumulate a decent pan-full of urine, the other way is to use a . . . .

Mordant, don’t try to use a mordent as this is a musical effect similar to a trill. No, what you need is Alum. I remember, long ago and far away, buying a large bag of the stuff, to dissolve in water to form a fire-retardant coating for some stage scenery I’d built. I doubt if you can acquire it so easily today. It’s poisonous, if you don’t use it the right way.